Basalt continuous filament insulating and fire-resistant material and sleeves and methods of construction thereof

ABSTRACT

An fire-retardant insulating material and method of construction thereof has a textile fabric fabricated of continuous basalt filaments. The continuous basalt filaments are preferably texturized or twisted. The insulating material may be arranged in any configuration, such as a sheet, panel or sleeve, and may be knit, woven or braided.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Ser. No. 60/796,395, filed May 1, 2006, which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to insulating materials, and more particularly to insulating materials and tubular sleeves constructed at least partially from basalt continuous filaments.

2. Related Art

Automotive, aeronautical, rail and marine components positioned in engine compartments or near heat sources such as exhaust manifolds may be subjected to harsh thermal environments. Further, undesired heat transfer may also occur between heat sources such as engines, exhaust systems and/or transmissions and the passenger compartment of an automobile, aircraft, train or boat. Oil and gas exploration and drilling tools also need protection from exposure to heat and spark and fire. It is known in the art to use insulating materials to form insulating panels or sleeves to reduce heat transfer from a heat source to other adjacent components. The insulating materials must be suitable for their intended use and are subject to testing under extreme conditions to insure their suitability. In the aerospace industry, for example, where temperature deviations are extremely large and components are unusually sensitive to temperature, the insulating materials must be capable of protecting components from especially harsh environments and conditions. These harsh environments may include exposure to open flames, so it is also beneficial if the insulating material is fire-resistant.

The prior art is replete with materials that are used as a heat insulating layer of such panels. For example, it is known to use various fibrous materials, and compositions of the same, to act as an insulating material of such panels or sleeves. Mineral fibers, such as fiberglass, silica, basalt and ceramic fibers are all known in the art as insulating materials. Each of these materials has different characteristics, for example, different physical and mechanical properties, operating temperature limits, thermal properties and chemical resistance, that make each material better suited for certain applications.

Modern engines run at higher temperatures than engines of several years ago and, accordingly, heat insulating materials for the modern engines are required to perform under more demanding conditions than those used in even the recent past. Some modern applications require protection to components in extreme temperatures that some of the prior art materials are incapable of providing. Thus, motor vehicle, aeronautical, train and boat manufacturers are required to use newer and more robust materials to provide adequate performance for such applications. Furthermore, many new demanding applications requiring protection against extreme heat have emerged due to the increased use of heat sensitive components (e.g., sensors) in close proximity to heat generating or conducting bodies.

SUMMARY OF THE INVENTION

A textile insulating material is fabricated at least in part from a plurality of texturized basalt continuous filaments. In accordance with various aspects of the invention, the texturized basalt continuous filaments can be knitted, woven and/or braided into a fabric, sleeve or other construction suited for the intended use. The fabric, sleeve or other construction can be coated with high temperature coatings, such as acrylic, polyester, urethane, epoxy, silicone and the like.

According to another aspect of the invention, a textile insulating material can be fabricated with a plurality of twisted basalt continuous filaments. The twisted basalt continuous filaments may, similarly to that of the texturized basalt continuous filaments mentioned above, be knitted, woven or braided into a fabric, sleeve or other construction suited for the intended use. The fabric, sleeve or other construction may be coated with high temperature coatings, such as acrylic, polyester, urethane, epoxy, silicone and the like.

In view of the above, the insulating materials fabricated in accordance with the invention have robust performance characteristics and are capable of providing protection to temperature sensitive components against extreme temperatures. The materials are also easily manipulated and capable of wide use throughout a vehicle by, for example, being capable of taking various shapes, and be formed into resilient constructions. In addition, the materials are generally economical in design, manufacture and use. The materials of the invention will find application in any of a number of fields including, without limitation, automotive, marine, aeronautical, train, and oil and gas exploration and drilling equipment.

Further scope of applicability of the present invention will become apparent from the following detailed description and claims. However, it should be understood that the detailed description and specific examples, while indicating presently preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects, features and advantages of this invention will become readily appreciated when considered in connection with the detailed description of presently preferred embodiments and best mode, appended claims and accompanying drawings, in which:

FIG. 1 is partial cross-sectional view of a textile material constructed using a plurality of basalt continuous filaments in accordance with one presently preferred embodiment of the present invention;

FIG. 2 is a fragmentary perspective view of a tubular closed wall textile sleeve constructed using a plurality of basalt continuous filaments in accordance with another presently preferred embodiment of the present invention;

FIG. 3 is a fragmentary perspective view of a tubular open wall textile sleeve constructed using a plurality of basalt continuous filaments in accordance with another presently preferred embodiment of the present invention; and

FIG. 4 is a fragmentary perspective view of another tubular textile sleeve constructed using a plurality of basalt continuous filaments in accordance with another presently preferred embodiment of the present invention.

DETAILED DESCRIPTION OF PRESENTLY PREFERRED EMBODIMENTS

Referring in more detail to the drawings, FIG. 1 illustrates a textile insulating material 10 constructed from a plurality of basalt continuous filaments 12 in accordance with one presently preferred embodiment of the invention. The basalt continuous filaments 12 are fire-resistant and can provide thermal protection against extremely high (e.g., 760° C.) and extremely low temperatures (e.g., −260° C.) as well. A fabric sheet, panel, sleeve or other construction fabricated with the interlaced continuous basalt filaments 12 in accordance with the invention is superior to, and may be used to supplement or replace, many insulating and fire-resistant materials in use today. As non-limiting examples, sleeves 14, 15, 16 are shown in FIGS. 2-4, respectively, wherein the sleeves 14, 15, 16 are fabricated at least in part from the basalt continuous filaments 12 and, thus, may be used to insulate pipes exposed to extremely high heat (such as exhaust pipes having temperatures of 500° C. to 760° C.) or insulate cryogenic pipes or tanks (such as liquid nitrogen or compressed natural gas tanks, which may reach temperatures as low as −191° C. and −161° C., respectively), for example.

According to one aspect of the present invention, a plurality of the basalt continuous filaments 12 are arranged to form a yarn or yarn-like strand 18. In one presently preferred embodiment, the yarn-like strand 18 is texturized to increase the volume of the strand 18 and create air pockets within the body of the strand 18. By texturizing the basalt continuous filament yarn 18, it can provide enhanced thermal protection with a reduced weight yarn, while also providing enhanced acoustic properties. In one presently preferred embodiment, the strand of yarn 18 is air-texturized and has a density of about 1800 tex. In another presently preferred embodiment, the strand of yarn 18 is subjected to a draw texturization rather than an air texturization. As such, the yarn 18 can be texturized to achieve any suitable density. Generally speaking, finer yarns 18 are used to make more flexible materials and heavier yarns 18 are used to provide increased coverage. Therefore, the choice of the yarn density, and the selection of the basalt filaments to be used depends on the type of material being constructed and the intended application for the resulting material. In yet another presently preferred embodiment, the strand of yarn 18 is twisted, instead of being texturized. In this construction, the yarn 18 has a density of about 260 tex and is twisted to 120 turns per meter, although any strand density and turns per meter may be used depending on the desired application. It has been found that the abrasion resistance of the insulating material increases as the degree of twisting increases. In yet another presently preferred embodiment, the strand 18 is first texturized, and then twisted. Many of these texturized and/or twisted basalt continuous filament yarns 18 are created and utilized to construct an insulating material of unitary construction, as described more fully below.

Having obtained a number of the basalt continuous filament strands of yarn 18, the strands 18 are then arranged in a configuration to create the desired structure of insulating material. In one embodiment, the strands 18 are woven to create the insulating material 10 or sleeves 14, 15, 16, however any method of construction can be used to interlace the strands 18, including but not limited to knitting, weaving, sewing, crocheting, embroidering and braiding. Depending on the application, one or more of the aforementioned methods of construction may be preferred. For example, in some instances, a braided texturized basalt continuous filament sleeve may be preferred for its ability to attain greater coverage and lighter weight.

Furthermore, the insulating textile material 10 may formed in any configuration, including but not limited to the textile fabric 10 and sleeves 14, 15, 16, wherein the sleeves 14, 15, 16 can have a continuous closed circumferential wall 20 (FIG. 2), or an open wall 20 (FIG. 3) construction with longitudinal edges 17, 19 preferably overlapping one another along the length of the sleeve 15. Further, the sleeves 14, 15, 16 may include one or more layers of insulating materials. By way of non-limiting example, as shown in FIG. 4, the insulating sleeve 16 may be created as a single layer knitted sleeve folded back onto itself to form the two layers 20, 22 of the sleeve 16, or a single layer knitted sleeve may be folded back and forth on itself to form the multi-layer sleeve. In addition, any of the sleeves 14, 15, 16 may be coated with a high temperature coating, such as illustrated generally at 21 in FIG. 2, that contains pigments if a color other than that of natural basalt is desired.

According to another aspect of the invention, layers, such as represented generally at 23 in FIG. 1, for example, in addition to the insulating layers 20 constructed of basalt continuous filament, may be present on the material 10 or sleeves 14, 15, 16. These additional layers 23 may include, for example, silicone, rubber, aluminum or other metal, epoxy, carbon-fiber, ceramic and plastic, or compositions thereof. As such, the insulating sleeves 14, 15, 16 can include the insulating layer or layers of woven or braided basalt continuous filaments 20 with the layer 23, for example, a silicone-rubber coating, applied to an exterior surface of the insulating material 20. In addition to the aforementioned material layers, other types of material layers may be used, such as in an application suitable for use of the described insulating material 10 and sleeves 14, 15, 16 to protect aircraft hoses from immediately bursting into flames when exposed to fire. In this application, the material 10 and/or sleeves 14, 15, 16 can be coated with an intumescent coating, represented generally at 25 in FIG. 3. The intumescent coating 25 can be adhered to the material 10 or sleeves 14, 15, 16 to provide additional insulation and fire resistance to the texturized basalt continuous filament sleeve 14, 15, 16. The intumescent coating 25 may be applied to only the outer-most surface of the sleeves 14, 15, 16 or material 10, or to all surfaces if desired.

The insulating and fire-resistant material 10 and sleeves 14, 15, 16 described above may be used in numerous applications. For example, the knitted, woven or braided sleeves 14, 15, 16 comprising basalt continuous filament yarn 18 may be used to insulate exhaust pipes to prevent extremely high heat produced by the exhaust pipe from damaging nearby temperature sensitive components in the vehicle. A knitted construction of the sleeve 14, 15, 16 is one preferred construction because it provides for easy installation, due to the fact that knitted yarns provide radial expandability to the wall or walls of the sleeve 14, 15, 16. As stated above, the basalt continuous filament yarn 18 may be texturized or twisted, with the texturized version being preferred in many applications.

The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from this description, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the spirit and scope of the invention as defined by the following claims. 

1. A fire-retardant insulating material, comprising: at least one layer of textile fabric constructed at least in part from a plurality of continuous basalt yarn filaments interlaced in a configuration such that continuous basalt filaments form a unitary construction.
 2. The insulating material of claim 1, wherein said configuration is a tubular sleeve.
 3. The insulating material of claim 2, wherein said tubular sleeve has a tubular inner wall surrounded by a tubular outer wall.
 4. The insulating material of claim 3 wherein said inner wall is fabricated of either a woven, knitted or braided fabric and said outer wall is fabricated of either a woven, knitted or braided fabric.
 5. The insulating material of claim 1, wherein said configuration is a woven fabric.
 6. The insulating material of claim 1, wherein said configuration is a knit fabric.
 7. The insulating material of claim 1, wherein said configuration is a braided fabric.
 8. The insulating material of claim 1, including at least another layer of material.
 9. The insulating material of claim 1 wherein said continuous basalt yarn filaments are texturized.
 10. The insulating material of claim 1 wherein said continuous basalt yarn filaments are twisted.
 11. The insulating material of claim 1 further comprising an intumescent coating adhered to said at least one layer of textile fabric.
 12. The insulating material of claim 1 further comprising a coating of silicone-rubber adhered to said at least one layer of textile fabric.
 13. A method of fabricating a fire-retardant insulating material, comprising: interlacing a plurality of continuous basalt yarn filaments with one another to form a textile fabric.
 14. The method of claim 13 further including performing said interlacing in a knitting process.
 15. The method of claim 13 further including performing said interlacing in a weaving process.
 16. The method of claim 13 further including performing said interlacing in a braiding process.
 17. The method of claim 13 further including fabricating said textile fabric as a tubular sleeve.
 18. The method of claim 17 further including constructing said tubular sleeve having a continuous closed circumferential wall.
 19. The method of claim 17 further including constructing said tubular sleeve having wall with overlapping edges extending along the length of the sleeve.
 20. The method of claim 13 further including adhering an intumescent coating to said textile fabric.
 21. The method of claim 13 further including adhering a coating of silicone-rubber to said textile fabric.
 22. The method of claim 13 further including texturizing said plurality of continuous basalt yarn filaments.
 23. The method of claim 22 further including twisting said plurality of continuous basalt yarn filaments after said texturizing.
 24. The method of claim 13 further including twisting said plurality of continuous basalt yarn filaments. 